Tire treatments are used to modify tire performance, especially for racing, by the application of chemicals after manufacturing. The current method or art for modifying the performance of tires is to apply various liquid chemicals that are predominately petroleum distillates, and/or coal tar distillates mixed in various proportions. These prior art tire treatments include Methyl Naphthalene (a commercially available blend of 1-Methylnaphthalene, 2-Methylnaphthalene and Naphthalene), mineral spirits, lacquer thinner, toluene, Xylene, Creosote, DEET (diethyl toluamide), automatic transmission fluid, WD-40, Naphthenic Solvents, Naphthenic Oils, Paraffinic Solvents, Paraffinic Oils, Aromatic Solvents, Aromatic Oils, Ethyl-Benzene, and various commercial blends of these chemicals and blends.
Many of these chemicals, currently used as racing tire treatments, are known carcinogens, suspect carcinogens, mutagens, teratogens, marine pollutants, highly flammable, or comprise other environmental pollutants and/or combinations thereof. Many of these chemicals used in prior art racing tire treatments have little or no biodegradability. Furthermore, many of these chemicals are routinely found in Superfund sites.
The desired modifications achieved by the use of these prior art chemicals may include lowering the durometer of the tire or alternatively to minimize the effect on durometer. At least some of these chemicals may be employed to clean the surface of the tire by removing foreign matter applied during manufacturing or clean the tire surface after the tire has been used, especially on a dirt track. At least some of these chemicals may be used to modify the adhesion of the tire to a given surface, including dirt, clay, asphalt, concrete or even surfaces that have been treated with a dried soft drink resin, such as dried Coca-Cola resin. Coca-Cola is a registered trademark of Coca-Cola Inc.
It is generally accepted that the above chemicals are to some degree effective. These chemicals and combinations thereof work in various ways and in combination of ways, all of which are not clearly understood.
One method is that solvents are chosen that are extremely good solvents for the components in the tires that are solvent soluble. The chosen solvents have a high enough vapor pressure so that they evaporate relatively quickly. During evaporation, these solvents draw chemicals out of the tires and leave other tire chemicals or components at a higher concentration than normal at the surface of an untreated tire. This gives a temporary advantage until the rubber with this higher concentration either wears off, or the temperature of the tire increases to a point that the chemicals at elevated levels themselves evaporate, or some combination of both.
Another method is to apply a neat or dilute chemical with lower volatility that mimics the components in the tires as supplied. This is the major use of Methylnaphthalene in treating tires. Other petroleum distillates and/or coal tar distillates are also employed to yield a similar effect.
Chemicals may be chosen because they purge the surface of loose particulate matter that may include tire particulate, clay, dirt or other matter that tires may pick up during racing or even in normal use.
In many cases, the methods employed for tire treatment reduce the life of the tire and the methods slowly destroy the structure or integrity of the composition of the tire.
The use of esters for prior art methods appears to be limited to phthalate esters.